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Objective-C: Where to remove observer for NSNotification?
...his is obviously not a satisfying answer.
I'd recommend, that you add a call [notificationCenter removeObserver: self] in method dealloc of those classes, which you intend to use as observers, as it is the last chance to unregister an observer cleanly. This will, however, only protect you against ...
MySQL “WITH” clause
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Update: MySQL 8.0 is finally getting the feature of common table expressions, including recursive CTEs.
Here's a blog announcing it: http://mysqlserverteam.com/mysql-8-0-labs-recursive-common-table-expressions-in-mysql-ctes/
Below is my earlier answ...
Nginx reverse proxy causing 504 Gateway Timeout
...nd it had to do with not using a keep-alive on the connection. I can't actually answer why this is but, in clearing the connection header I solved this issue and the request was proxied just fine:
server {
location / {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header ...
Keyboard shortcuts with jQuery
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Since this question was originally asked, John Resig (the primary author of jQuery) has forked and improved the js-hotkeys project. His version is available at:
http://github.com/jeresig/jquery.hotkeys
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Python: How to create a unique file name?
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I didn't think your question was very clear, but if all you need is a unique file name...
import uuid
unique_filename = str(uuid.uuid4())
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How to generate a random int in C?
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Note: Don't use rand() for security. If you need a cryptographically secure number, see this answer instead.
#include <time.h>
#include <stdlib.h>
srand(time(NULL)); // Initialization, should only be called once.
int r = rand(); // Returns a pseudo-random integer bet...
ElasticSearch - Return Unique Values
How would I get the values of all the languages from the records and make them unique.
5 Answers
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How do I get the type of a variable?
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I totally disagree. Java, C#, PHP, Perl, Python and so on were designed in C and C++ and they are not caterpillars. (When you create an database application to open variable tables from 'unknown' databases you need to control fiel...
When to encode space to plus (+) or %20?
...value is query value with a space, but the folder name in the path is literally foo+bar, not foo bar.
%20 is a valid way to encode a space in either of these contexts. So if you need to URL-encode a string for inclusion in part of a URL, it is always safe to replace spaces with %20 and pluses with ...
filtering NSArray into a new NSArray in Objective-C
... edited Jan 17 '18 at 6:45
Niall Kiddle
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answered Sep 21 '08 at 5:43
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